Most languages can be broken down into local dialects. It turns out that chimpanzee communication is no exception. I’m Jim Metzner, and this is the Pulse of the Planet, presented by DuPont.
We’re listening to chimpanzees recorded in the Gombi Reserve in Africa, and although chimps vocalize, they do most of their communication with gestures. That’s according to Roger Fouts, co-director of the Chimpanzee and Human Communication Institute at Central Washington University.
“Now we know, chimapanzees in the wild use gestures. Not only do they use gestures to communicate, but there are gestural dialects between communities. Gombi Stream if a chimp wants to be groomed, they raise one arm. In the Mahali Mountains, just about, 100 kilometers away, they use two hands to mean the same thing.”
So what influences a chimpanzee’s local dialect of gestures? Well, one factor might be changes within the local environment. For example, in Africa’s Cabali Forest, there’s been a problem with chimpanzees hands getting caught in snares. And as a result, chimps with injuries to their hands often walk on their wrists instead of their knuckles. And that may well have had an impact on the local gestural dialect, even with noninjured chimps.
“Recently at Cabali Forest we noted an adult male approached some infants, but rather than walking on his knuckles, he pulled his hands back and walked on his wrists. And approached them and played with them. Now normally because he was so aggressive they would’ve run away or stopped playing, but what he was doing, we think, was imitating a crippled chimp to show that he was less threatening.”
Finding and analyzing subtle differences in chimpanzee dialect takes many years. But it may also yield clues about the origins and diversity of human lanuage. Pulse of the Planet is presented by DuPont, bringing you the miracles of science, with additional support provided by the National Science Foundation.